1. Field of the Invention
The present invention generally relates to a method for manufacturing magnetoresistance elements. More particularly, the present invention relates to a method for manufacturing magnetoresistance elements having an improved yield rate.
2. Related Arts
Conventionally, as a means for detecting the rotation of a rotating body, a ferromagnetic thin film magnetoresistance element, whose resistance value varies according to the variation in the magnetic field of the rotating body due to the rotation of the multipolar magnets thereof (hereinafter referred to as "MR element"), has been known.
The MR element is integrated alone or with a transistor, etc., on a semiconductor substrate. As an element, the MR element is composed of a magnet thin film by forming a ferromagnetic material such as Ni-Co alloy, Ni-Fe alloy and Ni-Fe-Co alloy, into a film. When the magnetic thin film is patterned, shape magnetic anisotropy, due to shape effect, is added to the inherent magnetic anisotropy, and the magnetoresistance effect due to the shape magnetic anisotropy of the MR element is used as a sensor. The patterned magnetic thin film is completed as a product through an electric inspection in an inspection process where the patterned magnetic film is tested to determine whether it is defective. In this inspection process, the offset voltage is inspected and the middle point voltage of a bridge circuit constituted by the magnetic thin film is inspected.